Consolidated Statements of Shareholders' Equity - USD ($) $ in Thousands	Total	Ordinary Shares	Additional Paid-in Capital	Treasury Shares	Retained Earnings
Balance at Dec. 25, 2020	$ 411,689	$ 3	$ 399,311	$ (91,578)	$ 103,953
Balance, Shares at Dec. 25, 2020		27,907,077		4,437,439
Ordinary shares issued from exercise of stock options	2,381		2,381
Ordinary shares issued from exercise of stock options, shares		105,600
Ordinary shares issued from vesting of restricted share units	(667)		(667)
Ordinary shares issued from vesting of restricted share units, shares		30,423
Ordinary shares issued from employee share purchase plan	606		606
Ordinary shares issued from employee share purchase plan, shares		27,151
Share-based compensation expense	2,415		2,415
Net income	14,638				14,638
Balance at Mar. 26, 2021	431,062	$ 3	404,046	$ (91,578)	118,591
Balance, Shares at Mar. 26, 2021		28,070,251		4,437,439
Balance at Dec. 31, 2021	500,715	$ 3	417,438	$ (91,578)	174,852
Balance, Shares at Dec. 31, 2021		28,551,160		4,437,439
Ordinary shares issued from exercise of stock options	955		955
Ordinary shares issued from exercise of stock options, shares		42,753
Ordinary shares issued from vesting of restricted share units	(777)		(777)
Ordinary shares issued from vesting of restricted share units, shares		34,994
Share-based compensation expense	2,897		2,897
Net income	8,039				8,039
Balance at Apr. 01, 2022	$ 511,829	$ 3	$ 420,513	$ (91,578)	$ 182,891
Balance, Shares at Apr. 01, 2022		28,628,907		4,437,439